The present invention relates to methods using a synthetic molecular level device, such as a synthetic molecular spring, engine, or, machine, in a system, and more particularly, to a method using a synthetic molecular spring device in a system for dynamically controlling a system property, and a corresponding system thereof. Exemplary system properties used for describing and illustrating implementation of the present invention are momentum, topography, and electronic behavior. Using the synthetic molecular spring device for dynamically controlling each of these system properties is illustratively described with respect to several specific exemplary preferred embodiments of the corresponding system of the present invention.
Molecular structures featuring the capability of contracting or expanding, in a controllable fashion, under the action of an external triggering or activating mechanism are expected to become key components in the developing fields of nano-devices, material science, robotics, biomimetics, and molecular electronics. Particularly, molecular structures capable of exhibiting and/or causing directional motions, for example, linear and/or rotational directional motions, triggered or activated by appropriate triggering or activating signals are needed in order to construct molecular devices whose operation and function exhibit, or include, spring-like, engine-like, and/or machine-like, behavior.
In recent years, an increasing number of works and attempts to design, develop, and implement, synthetic molecular level devices, such as synthetic molecular springs, engines, and machines, have been presented. Several such teachings are: Bissell, R. A., Cordova, E., Kaifer, A. E., and, Stoddart, J. F., “A Chemically and Electrochemically Switchable Molecular Shuttle”, Nature 369, 133-137 (1994); Feringa, B. L., “In Control Of Molecular Motion”, Nature 408, 151-154 (2000); Jimenez, M. C., Dietrich-Buchecker, C., and Sauvage, J. P., “Towards Synthetic Molecular Muscles: Contraction and Stretching of a Linear Rotaxane Dimer”, Angewandte Chemie-International Edition in English 39, 3284-3287 (2000); Mahadevan, L. and Matsudaira, P., “Motility Powered by Supramolecular Springs and Ratchets”, Science 288, 95-99 (2000); Otero, T. F. and Sansinena, J. M., “Soft and Wet Conducting Polymers for Artificial Muscles”, Advanced Materials 10, 491-494 (1998); and, Tashiro, K., Konishi, K., and Aida, T., “Metal Bisporphyrinate Double-Decker Complexes as Redox-Responsive Rotating Modules, Studies on Ligand Rotation Activities of the Reduced and Oxidized Forms Using Chirality as a Probe”, Journal of the American Chemical Society 122, 7921-7926 (2000).
These teachings relate to such molecular structures in the form of rotaxane molecules, catenanes molecules, polypyrrole films, single-walled nanotube sheets, among others. Several teachings relating specifically to rotaxane molecules and/or catenanes molecules are: Leigh, D. A., Troisi, A., and, Zebetto, F., “A Quantum-Mechanical Description of Macrocyclic Ring Rotation in Benzylic Amide [2]-Catenanes”, Chemistry European Journal 7, 1450-1454 (2001); Amendola, V., Fabbrizzi, L., Mangano, C., and, Pallavicini, P., “Molecular Machines Based on Metal Ion Translocation”, Accounts of Chemical Research 34, 488-493 (2001); Collin, J. P., Dietrich-Buchecker, C., Gavina, P., Jimenez-Molero, M., and, Sauvage, J. P., “Shuttles and Muscles: Linear Molecular Machines Based on Transition Metals”, Accounts of Chemical Research 34, 477-487 (2001); Ashton, P. R. et al., “Dual-Mode ‘Co-Conformational’ Switching in Catenanes Incorporating Bipyridinium and Dialkylammonium Recognition Sites”, Chemistry European Journal 7, 3482-3493 (2001); and, Cardenas, D. J. et al., “Synthesis, X-ray Structure, and Electrochemical and Excited-State Properties of Multicomponent Complexes Made of a [Ru(Tpy)2]2+ Unit Covalently Linked to a [2]-Catenate Moiety. Controlling the Energy-Transfer Direction by Changing the Catenate Metal Ion”, Journal of the American Chemical Society 121, 5481-5488 (1999).
Yet, these teachings, either singly or in combination, do not provide a satisfactory realization of a complete set of prerequisites and characteristics critically important for practical commercial application of a molecular device, especially as part of a system featuring a system property amenable to dynamic control. Several such prerequisites and characteristics are: (1) capability of coupling to the macroscopic world, (2) capability of performing work, (3) modularity with respect to single or multi-dimensional scalability, (4) versatility, (5) robustness, (6) reversability, (7) operability in a continuous or discontinuous mode, (8) highly resolvable temporal response, and (9) capability of being monitored during operation by a variety of different techniques.
A machine is generally defined as a device, usually having separate entities, bodies, components, and/or elements, formed and connected to alter, transmit, and direct, applied forces in a predetermined manner, in order to accomplish a specific objective or task, such as the performance of useful work, or for controlling a particular property or properties of a system including the machine. An engine is generally defined as a device or machine that converts energy into mechanical motion, to be clearly distinguished from an electric, spring-driven, or hydraulic, motor operating by consuming an externally provided fuel.
Thus, a molecular structure, in the form of a chemical unit or module, featuring an interrelating collection of components and/or elements, that has the ability to store energy of predetermined chemical bonds in a particular molecular conformation, and convert the stored energy into mechanical motion, for performing useful work, or for dynamically controlling a particular property or properties of a system, in general, and a system, in particular, including the molecular structure, may be regarded as a molecular engine. In order to use such a molecular module as a whole or part of a molecular engine, it is necessary to control its action. One possibility relies on conditional formation and breakage of chemical bonds. Here, formation and breakage of chemical bonds translates to storage and release of potential energy, and concomitant molecular mechanical motion or movement. Although, it is quite common to find terms such as ‘molecular machines’, ‘molecular engines’, ‘molecular springs’, and other similar terms related to molecular structures and assemblies, in the prior art, practical implementation of the related mechanical properties, currently, is generally far from being demonstrated, for example, as highlighted by Amendola, V. et al., “Molecular Events Switched by Transition Metals”, Coordination Chemistry Reviews 190, 649-669 (1999).
The synthetic molecular spring device disclosed in PCT/US02/07178, filed Mar. 12, 2002, by the same inventors of the present invention, the teachings of which are specifically incorporated by reference as if fully set forth herein, generally features at least one synthetic molecular assembly and an activating mechanism, and exhibits multi-parametric controllable spring-type elastic reversible function, structure, and behavior, operable in a wide variety of different environments. As described therein, different types of the primary components, that is, each synthetic molecular assembly and the activating mechanism, may be selected from a wide variety of corresponding groups and sub-groups, while preserving the controllable spring-type elastic reversible function, structure, and behavior of the device.
A molecular device, such as the synthetic molecular spring device disclosed in PCT/US02/07178, whose operation and function exhibit, or include, spring-like, engine-like, and/or machine-like, behavior, featuring a molecular structure in the form of a scaleable chemical unit or module, can be effectively utilized as the critical component of a system needed for dynamically controlling a system property of the system. Ultimately, such a system, including the molecular device, can be incorporated into or integrated with the macroscopic world, for fulfilling the above indicated prerequisites and characteristics critically important for practical commercial application.
In the prior art, there are teachings of using a molecular device for controlling a system property of a system. In U.S. Pat. No. 6,212,093, issued to Lindsey, there is disclosed a molecular electronic device for high-density non-volatile memory, featuring a metal porphyrin in a sandwich coordination compound, as part of a molecular system, for controlling electrical properties. In Chemical Physics Letters, 265, 353-357 (1997), “An Electromechanical Amplifier Using A Single Molecule”, Joachim et al. describes a molecular electromechanical amplifier as part of a system featuring molecular level and macroscopic components. In that teaching, a fullerene molecule is used as a quantum dot and a metallic STM (scanning tunneling microscope) tip is used in order to apply mechanical forces on the fullerene molecule, thereby causing structural deformation and changing of the energy gap of the fullerene molecule.
Additional attempts of externally controlling a system property by using a molecular device are known, but they are typically impracticable for implementing in commercial applications because they lack the capability of directly and easily controlling the desired property at the molecular level. Other teachings in the prior art, such as those previously cited above, feature only general, non-detailed and non-enabling, indications and/or suggestions of utilizing a synthetic molecular level device, such as a synthetic molecular spring, engine, or, machine, in a system for controlling a system property. In the prior art, there is no teaching of a method for using a synthetic molecular device which exhibits the multi-parametric controllable spring-type elastic reversible function, structure, and behavior, of the synthetic molecular spring device disclosed in PCT/US02/07178, for dynamically controlling a system property, in general, such as momentum, topography, or electronic behavior, in particular, which has potential for commercial application.
There is thus a need for, and it would be highly advantageous to have a method using a synthetic molecular spring device in a system for dynamically controlling a system property, and a corresponding system thereof. Moreover, there is a need for such a method and corresponding system thereof, which are generally applicable to a wide variety of different fields and applications, for dynamically controlling a system property, such as momentum, topography, and electronic behavior, and which can be commercially implemented.